public class stream
{

    public stream()
    {
    }

    public stream(byte abyte0[])
    {
        buffer = abyte0;
        currentOffset = 0;
    }

    public byte readSignedByteA()
    {
        return (byte)(buffer[currentOffset++] - 128);
    }

    public byte readSignedByteC()
    {
        return (byte)(-buffer[currentOffset++]);
    }

    public byte readSignedByteS()
    {
        return (byte)(128 - buffer[currentOffset++]);
    }

    public int readUnsignedByteA()
    {
        return buffer[currentOffset++] - 128 & 0xff;
    }

    public int readUnsignedByteC()
    {
        return -buffer[currentOffset++] & 0xff;
    }

    public int readUnsignedByteS()
    {
        return 128 - buffer[currentOffset++] & 0xff;
    }

    public void writeByteA(int i)
    {
        buffer[currentOffset++] = (byte)(i + 128);
    }

    public void writeByteS(int i)
    {
        buffer[currentOffset++] = (byte)(128 - i);
    }

    public void writeByteC(int i)
    {
        buffer[currentOffset++] = (byte)(-i);
    }

    public int readSignedWordBigEndian()
    {
        currentOffset += 2;
        int i = ((buffer[currentOffset - 1] & 0xff) << 8) + (buffer[currentOffset - 2] & 0xff);
        if(i > 32767)
            i -= 0x10000;
        return i;
    }

    public int readSignedWordA()
    {
        currentOffset += 2;
        int i = ((buffer[currentOffset - 2] & 0xff) << 8) + (buffer[currentOffset - 1] - 128 & 0xff);
        if(i > 32767)
            i -= 0x10000;
        return i;
    }

    public int readSignedWordBigEndianA()
    {
        currentOffset += 2;
        int i = ((buffer[currentOffset - 1] & 0xff) << 8) + (buffer[currentOffset - 2] - 128 & 0xff);
        if(i > 32767)
            i -= 0x10000;
        return i;
    }

    public int readUnsignedWordBigEndian()
    {
        currentOffset += 2;
        return ((buffer[currentOffset - 1] & 0xff) << 8) + (buffer[currentOffset - 2] & 0xff);
    }

    public int readUnsignedWordA()
    {
        currentOffset += 2;
        return ((buffer[currentOffset - 2] & 0xff) << 8) + (buffer[currentOffset - 1] - 128 & 0xff);
    }

    public int readUnsignedWordBigEndianA()
    {
        currentOffset += 2;
        return ((buffer[currentOffset - 1] & 0xff) << 8) + (buffer[currentOffset - 2] - 128 & 0xff);
    }

    public void writeWordBigEndianA(int i)
    {
        buffer[currentOffset++] = (byte)(i + 128);
        buffer[currentOffset++] = (byte)(i >> 8);
    }

    public void writeWordA(int i)
    {
        buffer[currentOffset++] = (byte)(i >> 8);
        buffer[currentOffset++] = (byte)(i + 128);
    }

    public void writeWordBigEndian_dup(int i)
    {
        buffer[currentOffset++] = (byte)i;
        buffer[currentOffset++] = (byte)(i >> 8);
    }

    public int readDWord_v1()
    {
        currentOffset += 4;
        return ((buffer[currentOffset - 2] & 0xff) << 24) + ((buffer[currentOffset - 1] & 0xff) << 16) + ((buffer[currentOffset - 4] & 0xff) << 8) + (buffer[currentOffset - 3] & 0xff);
    }

    public int readDWord_v2()
    {
        currentOffset += 4;
        return ((buffer[currentOffset - 3] & 0xff) << 24) + ((buffer[currentOffset - 4] & 0xff) << 16) + ((buffer[currentOffset - 1] & 0xff) << 8) + (buffer[currentOffset - 2] & 0xff);
    }

    public void writeDWord_v1(int i)
    {
        buffer[currentOffset++] = (byte)(i >> 8);
        buffer[currentOffset++] = (byte)i;
        buffer[currentOffset++] = (byte)(i >> 24);
        buffer[currentOffset++] = (byte)(i >> 16);
    }

    public void writeDWord_v2(int i)
    {
        buffer[currentOffset++] = (byte)(i >> 16);
        buffer[currentOffset++] = (byte)(i >> 24);
        buffer[currentOffset++] = (byte)i;
        buffer[currentOffset++] = (byte)(i >> 8);
    }

    public void readBytes_reverse(byte abyte0[], int i, int j)
    {
        for(int k = (j + i) - 1; k >= j; k--)
            abyte0[k] = buffer[currentOffset++];

    }

    public void writeBytes_reverse(byte abyte0[], int i, int j)
    {
        for(int k = (j + i) - 1; k >= j; k--)
            buffer[currentOffset++] = abyte0[k];

    }

    public void readBytes_reverseA(byte abyte0[], int i, int j)
    {
        for(int k = (j + i) - 1; k >= j; k--)
            abyte0[k] = (byte)(buffer[currentOffset++] - 128);

    }

    public void writeBytes_reverseA(byte abyte0[], int i, int j)
    {
        for(int k = (j + i) - 1; k >= j; k--)
            buffer[currentOffset++] = (byte)(abyte0[k] + 128);

    }

    public void createFrame(int id)
    {
        buffer[currentOffset++] = (byte)(id + packetEncryption.getNextKey());
    }

	private static final int frameStackSize = 10;
	private int frameStackPtr = -1;
	private int frameStack[] = new int[frameStackSize];
	public void createFrameVarSize(int id)	// creates a variable sized frame
	{
		buffer[currentOffset++] = (byte)(id + packetEncryption.getNextKey());
		buffer[currentOffset++] = 0;		// placeholder for size byte
		if(frameStackPtr >= frameStackSize-1) {
			throw new RuntimeException("Stack overflow");
		}
		else frameStack[++frameStackPtr] = currentOffset;
	}
	public void createFrameVarSizeWord(int id)	// creates a variable sized frame
	{
		buffer[currentOffset++] = (byte)(id + packetEncryption.getNextKey());
		writeWord(0);		// placeholder for size word
		if(frameStackPtr >= frameStackSize-1) {
			throw new RuntimeException("Stack overflow");
		}
		else frameStack[++frameStackPtr] = currentOffset;
	}

	public void endFrameVarSize()	// ends a variable sized frame
	{
		if(frameStackPtr < 0) throw new RuntimeException("Stack empty");
		else writeFrameSize(currentOffset - frameStack[frameStackPtr--]);
	}

	public void endFrameVarSizeWord()	// ends a variable sized frame
	{
		if(frameStackPtr < 0) throw new RuntimeException("Stack empty");
		else writeFrameSizeWord(currentOffset - frameStack[frameStackPtr--]);
	}

    public void writeByte(int i)
    {
        buffer[currentOffset++] = (byte)i;
    }

    public void writeWord(int i)
    {
        buffer[currentOffset++] = (byte)(i >> 8);
        buffer[currentOffset++] = (byte)i;
    }

    public void writeWordBigEndian(int i)
    {
        buffer[currentOffset++] = (byte)i;
        buffer[currentOffset++] = (byte)(i >> 8);
    }

    public void write3Byte(int i)
    {
        buffer[currentOffset++] = (byte)(i >> 16);
        buffer[currentOffset++] = (byte)(i >> 8);
        buffer[currentOffset++] = (byte)i;
    }

    public void writeDWord(int i)
    {
        buffer[currentOffset++] = (byte)(i >> 24);
        buffer[currentOffset++] = (byte)(i >> 16);
        buffer[currentOffset++] = (byte)(i >> 8);
        buffer[currentOffset++] = (byte)i;
    }

    public void writeDWordBigEndian(int i)
    {
        buffer[currentOffset++] = (byte)i;
        buffer[currentOffset++] = (byte)(i >> 8);
        buffer[currentOffset++] = (byte)(i >> 16);
        buffer[currentOffset++] = (byte)(i >> 24);
    }

    public void writeQWord(long l)
    {
        buffer[currentOffset++] = (byte)(int)(l >> 56);
        buffer[currentOffset++] = (byte)(int)(l >> 48);
        buffer[currentOffset++] = (byte)(int)(l >> 40);
        buffer[currentOffset++] = (byte)(int)(l >> 32);
        buffer[currentOffset++] = (byte)(int)(l >> 24);
        buffer[currentOffset++] = (byte)(int)(l >> 16);
        buffer[currentOffset++] = (byte)(int)(l >> 8);
        buffer[currentOffset++] = (byte)(int)l;
    }

    public void writeString(java.lang.String s)
    {
        s.getBytes(0, s.length(), buffer, currentOffset);
        currentOffset += s.length();
        buffer[currentOffset++] = 10;
    }

    public void writeBytes(byte abyte0[], int i, int j)
    {
        for(int k = j; k < j + i; k++)
            buffer[currentOffset++] = abyte0[k];

    }

    public void writeFrameSize(int i)
    {
        buffer[currentOffset - i - 1] = (byte)i;
    }

    public void writeFrameSizeWord(int i)
    {
        buffer[currentOffset - i - 2] = (byte)(i >> 8);
        buffer[currentOffset - i - 1] = (byte)i;
    }

    public int readUnsignedByte()
    {
        return buffer[currentOffset++] & 0xff;
    }

    public byte readSignedByte()
    {
        return buffer[currentOffset++];
    }

    public int readUnsignedWord()
    {
        currentOffset += 2;
        return ((buffer[currentOffset - 2] & 0xff) << 8) + (buffer[currentOffset - 1] & 0xff);
    }

    public int readSignedWord()
    {
        currentOffset += 2;
        int i = ((buffer[currentOffset - 2] & 0xff) << 8) + (buffer[currentOffset - 1] & 0xff);
        if(i > 32767)
            i -= 0x10000;
        return i;
    }

    public int readDWord()
    {
        currentOffset += 4;
        return ((buffer[currentOffset - 4] & 0xff) << 24) + ((buffer[currentOffset - 3] & 0xff) << 16) + ((buffer[currentOffset - 2] & 0xff) << 8) + (buffer[currentOffset - 1] & 0xff);
    }

    public long readQWord()
    {
        long l = readDWord() & 0xffffffffL;
        long l1 = readDWord() & 0xffffffffL;
        return (l << 32) + l1;
    }

    public java.lang.String readString()
    {
        int i = currentOffset;
        while(buffer[currentOffset++] != 10) ;
        return new String(buffer, i, currentOffset - i - 1);
    }

    public void readBytes(byte abyte0[], int i, int j)
    {
        for(int k = j; k < j + i; k++)
            abyte0[k] = buffer[currentOffset++];

    }

    public void initBitAccess()
    {
        bitPosition = currentOffset * 8;
    }

	public void writeBits(int numBits, int value)
	{
		int bytePos = bitPosition >> 3;
		int bitOffset = 8 - (bitPosition & 7);
		bitPosition += numBits;

		for(; numBits > bitOffset; bitOffset = 8) {
			buffer[bytePos] &= ~ bitMaskOut[bitOffset];		// mask out the desired area
			buffer[bytePos++] |= (value >> (numBits-bitOffset)) & bitMaskOut[bitOffset];

			numBits -= bitOffset;
		}
		if(numBits == bitOffset) {
			buffer[bytePos] &= ~ bitMaskOut[bitOffset];
			buffer[bytePos] |= value & bitMaskOut[bitOffset];
		}
		else {
			buffer[bytePos] &= ~ (bitMaskOut[numBits]<<(bitOffset - numBits));
			buffer[bytePos] |= (value&bitMaskOut[numBits]) << (bitOffset - numBits);
		}
	}

    public void finishBitAccess()
    {
        currentOffset = (bitPosition + 7) / 8;
    }

    public byte buffer[] = null;
    public int currentOffset = 0;
    public int bitPosition = 0;

    public static int bitMaskOut[] = new int[32];
	static {
		for(int i = 0; i < 32; i++)
			bitMaskOut[i] = (1 << i) - 1;
	}

    public Cryption packetEncryption = null;

}
